Some electrical connection boxes mounted in an automobile have a structure in which a circuit component is housed in a case. The circuit component includes a circuit board, a busbar arranged along a back surface of the circuit board, and a switching member such as a relay mounted to a front surface of the circuit board, and the busbar has a terminal portion formed by bending an end thereof into a substantially L shape. The case includes a frame placed along a peripheral edge of the circuit board and secured to the circuit board, and a cover assembled to the frame so as to cover the circuit board from the front surface. A connector housing is mounted to the frame so as to face an outer peripheral side of the frame, and the terminal portion of the busbar is housed in the connector housing. When a harness connector fits in the connector housing, a terminal of the harness connector is connected to the terminal portion of the busbar.
For the above described electrical connection box, water may enter the inside of the frame from outside through a clearance between the connector housing and the cover.
Thus there is a need in the art for an electrical connection box that prevents or limits liquid from entering through a clearance between a connector housing and a cover.